Process of working natural sodium sulphate deposits



Mai-ch 25, 1930. G. F. ANDERSEN PROCESS OF WORKING NATURAL SODIUM SULPHATE DEPOSITS Filed Nov. 12, 1928 INVENTOR Geagye i? Alida/sen G iz] 6 W ATTORNEY Patented Mar. 25, 13 O PATENT OFFICE GEORGE E. ANDEB-SEN, OF SEATTLE, VIALEEIINGTOE, ASS GNOR, BY DIRECT AND MESNE ASSIGNMENTS, TO WELTHA PROCESS CORPOBATIOZJ, OF SEATTLE, WASHINGTON,

A CORPORATION OF \VASHINGTON PROCESS OF WORKING NATUBAL SODIUM SULPHATE DEPOSITS Application filed November 12, 1928. Serial No. 318,897.

My invention relates to improvements in processes for working natural sodium sulphate deposits and the object of my invention is to devise a process by which natural 5 sodium sulphate deposits'may be worked at low cost and by which a high grade and very nearly pure sodium sulphate maybe produced.

At present a large part of the sodium sulphate which is used commercially is produced as a by-product in the manufacture of hydrochloric acid and can be offered for sale much cheaper than the natural sodium. This by-product usually contains a relatively high percentage of insolubles and is not as good a grade of sodium sulphate as it is possible to produce by the use of my process from the natural deposits of sodium sulphate.

In a general way myprocess consists in utilizing the forces and agencies of nature and in regulating the conditions under which natural reactions take place in such a manner as to cause the natural sodium sulphate to be formed in a substantially pure state and at a very low cost.

In many natural sodium sulphate deposits which occur in lakes or ponds in which water accumulates in wet seasons the sulphates are found in columns and these columns are ususo ally embedded in and surrounded by silt. This silt is usually deposited over the top of the whole lake or deposited periodically and is thus spread over what is then the tops of the columns, after which the columns continue to form on the top of the layer of silt directly above the previously formed columns. The result of this process is that the columns I of sodium sulphate have layers of silt embedded therein and the space between the columns is filled with silt and the actual sodium sulphate deposits are necessarily impregnated with silt and insoluble matter making it diflicult and expensive to recover the sodium sulphate and put the same in shape for the market.

In a general way my process consists in excluding the silt and solid matter from the lakes or deposits or from certain desired areas within said lakes or deposits so as to permit the natural formation of the columns of sodium sulphate in an environment free from silt and insoluble impurities, the result being that substantially pure sodium sulphate or salt cake will be deposited. This sodium sulphate will not require any refining or purifying but will be ready for the market in the condition in which it is harvested or gathered thus making a process by which a very high grade product can be produced very cheaply after the initial installation. It is essential to the success of the process that the same be carried out at the location or lake in which the deposits are formed by nature and that the natural conditions necessary to the formation of a high grade substantially pure product shall not be interfered with except to remove undesirable features. I prefer to exclude the silt by providing a silt proof Wall around the area being worked but do not limit myself to this method of excluding said silt.

' In the accompanying drawings I have illustrated more or less diagrammatically one general form of apparatus and method which may be used in carrying out my process.

In said drawings Figure 1 is a somewhat diagrammatic view in vertical section illustrating one preferred method of carrying out my process.

Fig. 2 is a plan view of the same.

Fig. 3 is a sectional view showing a method of working an entire lake in which sodium sulphate deposits are formed.

In the drawings 5 designates a depression or lake which constitutes a natural sodium sulphate deposit, 6 are columns of sodium sulphate which have been formed by processes of nature within said lake and 7 are layers of silt and insoluble matter which have been laid down periodically on the tops of the, then formed, columns and S designates silt which has filled in between the columns. The drawing shows that the sodium sulphate columns continue to form in vertical alignment regardless of the presence of the lay ers 7 of silt each deposit forming directly above the preceding one.

In accordance with my invention I provide an enclosure or enclosing wall 9, which may be in the nature of a col erdam sunk into the moving the s-ilt and undesirable solid matter which lies underneath and within the walls, leaving the columns of sodium sulphate standing, or trench maybe dug to the proper dimensions and depth anc the enclosure built from the bottom upward after which the silt within the walls may be removed, by any method, leaving the sodium sulphate columns standing. 7 The walls are necessarily high enough above the surface so that water can not flow over the top of the same during high Water periods.

'Any desired area which is to be worked may be enclosed by the'silt excluding wall, for instance an entire lake 11 may be enclosed within a wall 12 as shown in Fig. 3.

' A trench 13 is preferably formed just outside the wall 12 to catch water which runs to ward said lake and this water may be fed through into the lake in any suitable manner. Care is taken to construct the wall so as i not to obstruct or, in any way interfere with the natural, surface or subterranean, flow of sulphates or sulphate brine to the location.

of the deposit. To assist in the formation of the desired product the brine may be pumped into the receptacle 10 and additional water may be supplied during dry seasons.

The foregoing description and accompanying drawings clearly disclose a preferred method of carrying out my invention but it will be understood that changes in the which consists in removing the silt and foreign matter from predetermined areas in said deposits, excluding the furtherentrance of silland foreign solid matter from said areas and permitting the natural formation and 7 growth of columns of sodium sulphate in these areas from natural sodium' sulphate brine.

4. The process of obtaining substantially pure sodium sulphate from a natural sodium sulphate deposit, which consists in surrounding an enclosure within said deposit by silt proof walls, removing the silt and foreign matter fromsaid enclosure, and admitting the natural sodium sulphate brine into said enclosure whereby the sodium sulphate will be formed fromsaid brine in an environment free from foreign matter. i j- 5. The process of obtaining sodium sulphate from a lake in which said sodium sul- '1 phate forms in'vertical columns, which consists in enclosing'a predetermined areawithin said lake by silt proof walls, removing the 7 il from between the columns within said free brine from the lake into said enclosure ber, 1928.

GEORGE F. "ANDERSEN.

method and apparatus may be resorted to within the scope and spirit of the following claims.

I claim:

1. The process of obtaining sodium sulphate from natural sodium sulphate deposits, which consists in excluding the silt and foreign matter from said deposits and permitting the natural formation of the sodium sulphate from natural sodium sulphate brine.

2. The process of obtaining sodium sulphate in a substantially pure form from natural sodium sulphate deposits, which consists in excluding solids and insoluble matter from predetermined areas and permitting the sodium sulpnate to be formed in these areas from natural sodium sulphate brine.

3. Theprocess of obtaining substantially pure sodium sulphate on'a commercial scale, from natural sodium sulphate deposits,

t enclosed area, and admittingithe natural silt V 

